This is an excerpt from EERE Network News, a weekly electronic newsletter.

September 22, 2004

Study Finds Vulnerabilities in the U.S. Power Grid

A recent study of the U.S. power grid finds that a major disruption could result from the loss of only two percent of its electrical substations. The study, conducted by researchers at Penn State and DOE's National Renewable Energy Laboratory, involved mathematically modeling the electrical grid with more than 14,000 "nodes" at which either generators or substations are located. The study found that during a cascading failure, in which heavily loaded substations fail in sequence, the failure of only about 280 of the most heavily loaded substations could cause a catastrophic failure of the entire grid. In contrast, a random failure of about 411 substations would result in a loss of power for only 60 percent of the electrical grid. The authors suggest that schemes to reduce the electrical load on the most heavily loaded substations could reduce the electrical system's overall susceptibility to disruptions. The study was published in the February 26th edition of Physical Review E; Penn State announced the news on September 16th. See the Penn State press release.